Garry Shandling was a stand-up comedian, screen and television actor, director, writer and producer who was nominated for 19 Primetime Emmy Awards and two Golden Globe Awards as the star in It's Garry Shandling's Show and The Larry Sanders Show.

At age 66, with little warning, he died of a sudden massive heart attack. He had no previous heart attack warnings and had not consulted a doctor for more than a year. Three days before his heart attack, he was seen out on the town with old friends Kathy Griffin and Bob Odenkirk. The day before he died, he complained of shortness of breath and chest pains to a doctor-friend who visited him at his home. The doctor told him that if he wasn't feeling better by the next day to go to an emergency room. The next morning at 10:30 AM, while calling 911, he fell on the floor unconscious. Paramedics rushed to his home. Since no one answered the bell, they broke the door down and found him unconscious but with his heart still beating. He was rushed to St. John's Hospital in Santa Monica, but had died before they got him there.

Clues to the Cause of His Death

Why would this man get a sudden fatal heart attack at the relatively young age of 66? He was not overweight. He was very fit, played basketball and boxed four times a week. He owned the Wildcard West Boxing Gym in Santa Monica and had a basketball court at his home.

In April 2015, 11 months before his death, he backed his Porsche into a parked Prius, stopped and got out of his car, took a photo of the Prius and then left without leaving a note to the owner of the damaged car. This was strange behavior for man who never before had any known trouble with the law.

Three months before his death, he was on "Comedians in Cars Getting Coffee" and told the host, Jerry Seinfeld, that he had a hyperactive parathyroid gland. The parathyroid glands control calcium levels that control messages along nerves that regulate heart beats and mind function. An overactive parathyroid can cause bone fractures, kidney stones, mood disorders, loss of memory, dementia . . . and heart attacks.

Gary Shandling's overactive parathyroid gland produced excess parathyroid hormone. Excess parathroid hormone raises blood calcium levels and acts directly on bones to damage them and cause inflammation (Mediators of Inflammation, March 23, 2014). Everyone usually has four parathyroid glands located near the thyroid gland in the front of the neck. Shandling could have consulted a specialist who would have removed one overactive parathyroid gland and he would have been cured.

Never Ignore a High Blood Calcium Test

A blood calcium test is part of routine blood tests done on normal physical exams. If your doctor ever tells you that your blood calcium is high, make sure that you find a cause. The most common cause of high blood calcium is a parathyroid tumor that usually can be removed and cured. All of the other causes are far less common; they include:

A hidden cancer, such as lung, breast or kidney cancer, squamous cell skin cancer or multiple myeloma, can cause high calcium, but this is rare and usually occurs only after the cancer has spread through the body.

Please note that you can have a parathyroid tumor even if your blood calcium level is normal. I think everyone who has kidney stones, or any of the other symptoms of an overactive parathyroid listed above, should get a blood test for parathyroid hormone.

How Inflammation Leads to a Heart Attack

Plaques form in arteries when an overactive immunity, called inflammation, punches holes in the inner lining of arteries. The holes bleed and clot and then a plaque starts to form. Heart attacks are not caused by the plaques themselves. A heart attack occurs when a piece of plaque breaks off from the artery wall, which causes a clot to form at the injured spot. The clot extends to block all blood flow to part of the heart muscle. The heart muscle's sudden complete lack of oxygen causes that part of the muscle to hurt and die. After the start of a heart attack, a person has only about 90 minutes to get to a hospital and have a tube inserted into the blocked artery to open the artery and allow blood to flow to the damaged heart muscle. Otherwise, the oxygen-starved heart muscle dies and is replaced by scar tissue. Anything that causes chronic inflammation can lead to a heart attack.

What Increases Risk for Inflammation?

I cannot be certain that Shandling's hyperactive parathyroid caused his heart attack, but it is a known cause of inflammation. His heart attack could have been caused by any one of the many sources of inflammation. Scientists have not worked out all the mechanisms, but anything that damages cells in your body causes inflammation. This may explain why many unhealthful lifestyle habits are associated with increased risk for heart attacks, cancers and other diseases:

About the Author: Gabe Mirkin, MD

Sports medicine doctor, fitness guru and long-time radio host Gabe Mirkin, M.D., brings you news and tips for your healthful lifestyle. A practicing physician for more than 50 years and a radio talk show host for 25 years, Dr. Mirkin is a graduate of Harvard University and Baylor University College of Medicine. He is board-certified in four specialties: Sports Medicine, Allergy and Immunology, Pediatrics and Pediatric Immunology. The Dr. Mirkin Show, his call-in show on fitness and health, was syndicated in more than 120 cities.
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